Theft of motor vehicle or of motor vehicle parts are currently on the rise in North Americ, due to economic recession. Various theft-deterring systems have been devised for preventing unauthorised ignition of the motor engine from the motor vehicle proper, some of the most recent of which have become quite effective. Unfortunately, these systems, while preventing a burglar from departing with the whole vehicle, do not prevent those burglars from detaching and pulling vehicle parts out from the vehicle, for example, the wheels.
Fleets of commercial vehicles in large parking spaces are among the preferred targets of burglars, during overnight periods. These commercial vehicles, for example pick-up trucks with expensive materials loaded inside the topper, are prime targets, particularly the content of the topper proper which is supported over the rear box of the pick-up truck. Obviously, it would be preferable that, at the end of each day, the topper be detached and released from the pick-up truck for storing at a separate location where security would be much tighter. An added advantage would be that the pick-up truck, free of the topper, could be used for alternate purposes, which would enhance efficiency of operations. Moreover, it often happens that, in large van fleets, e.g. of utility companies, a specific van with tools and equipment is assigned to a specific drivertechnician. A problem arises when the vehicle requires repairs or servicing, putting out of commission not only the vehicle but also the tools, the equipment and the driver.
Unfortunately, the complexity of current securing means for securing the topper to the pick-up truck box is high, and release thereof usually requires specialized tools and at least two workers. This in effect discourages daily removal of the topper loaded pick-up truck, especially with large commercial fleets.
Among the prior art, U.S. Pat. No. 3,868,088 issued in 1975 to Reeves teaches that it is known to provide a Jack assembly for raising a topper 24 from the box 36 of a pick-up truck 10, in view of releasing the topper from the truck by moving the latter forward. This jack assembly consists of two pairs of self-standing upright side legs 50, 50 having inturned horizontal cylindrical elbows 20. Elbows 20 releasably engage cylindrical channels 22 in mounting brackets 26 at the exterior front and rear lateral side wall portions of the topper 24.
U.S. Pat. Nos. 4,648,649 issued in 1987 to Beal, and No. 4,815,787 issued in 1989 to Hale, teach means for releasably anchoring a topper to the top edge of the side walls of a pick-up truck box. These toppers are of the open type, i.e. that they do not include an integral bottom flooring and stop about the top edge level of the side walls of the pick-up truck box.
The Beal reference is interesting in that it discloses in FIG. 4 a cam fastener 50, operatable from the inside of the topper enclosure 10, to releasably anchor the top horizontal edge portion 18 of the side wall 15 of a pick-up truck box, through a dovetail Joint type assembly of rail members 20, 23. By rotating the bolt part 35 of the cam fastener 50 through its top head 50 located inside the topper enclosure 10, rails 20, 23 may be released from one another, to release the topper 10 from the truck 15. When cam fastener 50 interlocks rails 20 and 23, and by closing and locking the tail gate 17 of the pick-up truck, the topper 20 becomes a self-enclosed structure. Unauthorized access to the topper enclosure, and thus to interior cam fasteners 50, is thus prevented, whereby unauthorized release of the topper from the box is also prevented.
U.S. Pat. No. 3,572,821 issued in 1971 to Van Antwerp discloses a rocking fastener 34 for securing a tarpaulin 27 over the box 14 of a pick-up truck 12. Each fastener 34 is pivotally carried by fore and aft extending horizontal rods 31 and 32, extending proximate the side walls 18 of the pick-up truck box 14, inside the latter. The lower end of fastener 34 carries a hook 40 pivotally biased by spring 37 toward the corresponding box side wall 18, to automatically hookingly engage the downturned inner flange 16 of the top edge portion 15 of side wall 13. Again, upon closing tail gate 20, a self-enclosed area is achieved inside topper enclosure 14.
U.S. Pat. No. 5,018,777 issued in May 1991 to Swenson, Grove & Grove, is directed more particularly to a hinged fastener 70 for preventing unauthorized release of a topper from a pick-up truck box. Fastener 70 includes an upper arm 72, integral to the topper side wall bottom edge portion 27, and a lower arm 52, integral to the top edge of the box side wall 17, a hinge mount 86 interconnecting arms 52 and 72, and a padlock 73 operated by a cylinder key 76. The padlock cylinder 75 opens into the topper enclosure.